B7800 gets hot after about a hour.

[Rob 80]

When using the bush hog after about a hour or hour and a half the tractor gets hot.

The radiator is clean and full, air filter is clean what would cause this?

I think the bush hog is to much for it it's a 5 foot bush hog and i am going really slow 2,3 mph it seems to only get hot when i cut the thick heavy tall stuff.

Would being under powered cause it to heat up? I do not go fast so it does not bog down.

 

[jaxs]

5' is too large in anything other than sparse weeds. Regardless of reason,you should address it before ruining the engine. Diesel will preform where gas can't but overheating will quickly destroy a diesel whereas a gasoline might be uneffected or only slightly damaged. I'm a proponent of monitoring exhaust temperatures so that load can be reduced before engine overheats.

 

[CH4Ohio]

Is your fan belt tight and in good shape? Easy to overlook a sloppy or loose fan belt.

I have essentially the same tractor and never had trouble with a 5' bush hog. Though, like you, have to take it slow and pick it up a few inches in really heavy stuff. You can always take less than a full width pass until you get it knocked down.

Grill panels need to be clean. Screens in front of radiator clean. Radiator clean (better to blow it out than flush with water, I think). Fan needs to be intact, and fan belt tight. Those are the basics and sounds like you're already on it.

 

[Thomas]

"air filter is clean what would cause this?"
It doesn't help.

"The radiator is clean and full"
The very bottom where it could pack in for blowing or washing.

HST or gear...sounds you need to go slower in the thick stuff.

 

[RjCorazza]

Another item to consider is the water pump. Check the weep hole for leaking, and it's also possible the impeller blades are corroded off.
That said, the most frequent issue is an externally clogged radiator - it's not always obvious, so shine a light through the fins.

 

[rScotty]

I scrub the radiator fins lightly with a soft brush while gently spraying soapy water from the engine side. Amazing how much dirt comes out the front, how clean the fins get, and how much better it cools.

Something not always mentioned is to make sure that the side panels or rubber foam or whatever the factory had there is still sound and in place so that the fan is drawing air through the radiator instead of in from the sides. HUGE difference.

But clean isn't a cure-all. My feeling is that you are borderline to start with working that bush hog on your B7800. I'd reduce the load on the engine while it's still good.

 

[Have tractor did travel]

My B3200 is the unit that replaced your B7800. I pull a 60" bush hog through heavy stuff with no issues, so I do not think 60" is oversized for your tractor.

Be sure your bush hog is set that the front is lower than the back If you are cutting brush, ok for blades to be dull. If cutting grass and weeds, better for blades to be sharp.

Others have addressed the engine and cooling with more expertise than I can bring to the game.

 

[zoltanthegypsy]

+1 for a loose fan belt among other things to check. Had this happen on my BX. Belt wears "skinny" and fan spins but not fast enough. Also happened to my neighbor and his older larger Kubota. Looks like it's working but doesn't move enough air.

 

[Hay Dude]

Rinse radiator with a strong stream of water for about 15-20 minutes
Squirt water straight through being careful not to bend fins.
Youll see what looks like chocolate milk coming out

 

[5030]

Get yourself a 'Radiator Genie' and use that. On Amazon. I have one, works very well rinse from the engine side toward the grill.